Novel imaging in advanced prostate cancer

Prostate cancer (PCa) is the most commonly diagnosed noncutaneous cancer and second leading cause of death in men. Imaging evaluation of PCa is challenging because of the prostate's deep pelvic location, its complex zonal anatomy and its multifocal nature. Novel imaging modalities are needed to improve detection, reassessment in biochemical relapse, and disease progression in advanced metastatic stages.

Current imaging modalities have distinct strengths. However, all lack the ability to diagnose micrometastases, differentiate high from low-grade disease and diagnose advanced disease, especially at low prostate specific antigen values. There is a need to combine the existing imaging methods with concepts utilizing tumor biology to differentiate biologically aggressive from indolent tumors. PET imaging with novel tracers facilitate improved imaging of PCa, but also usher in new compounds that could be useful for directing treatment as well. Most tracers have limited sensitivity, with the exception of prostate-specific membrane antigen (PSMA)-targeting tracers, that offer relatively higher sensitivity and specificity.

PSMA-PET appears promising in improving the imaging yield particularly in recurrent and advanced disease states. Incorporating PSMA-PET in these settings could open or prolong windows along the trajectory of the disease that could allow new treatments or more effective use of currently existing treatments. Prospective studies focusing on novel imaging enhancement and integration with therapeutic applications are needed.